title: Identification of a region responsible for binding to the cell wall within the S-layer protein of Clostridium thermocellum.
abstract: The protomer forming the S-layer of Clostridium thermocellum was identified as a 140 kDa protein which was non-covalently bound to the cell wall. Cloning and sequencing of the corresponding gene revealed an open reading frame of 3108 nucleotides encoding a polypeptide of 1036 amino acids, termed SlpA. The amino acid composition of SlpA matches the composition of a previously described exocellular glycoprotein. SlpA shared extensive similarity with the S-layer protein of Bacillus sphaericus and with the outer wall protein of Bacillus brevis. In addition, the amino-terminal region of SlpA contained a segment presenting similarities with segments termed SLH (S-layer homologous), which are found in several bacterial exoproteins. A polypeptide of 209 residues comprising this segment was shown to bind to cell walls extracted from C. thermocellum cells.
authors.affiliation: Unité de Physiologie Cellulaire and URA 1300 CNRS, Département des Biotechnologies, Institut Pasteur, 28 rue du Dr Roux, 75724 Paris Cedex 15, France.
authors.forename: Marc
authors.initials: M
authors.lastname: Lemaire
authors.affiliation: Unité de Physiologie Cellulaire and URA 1300 CNRS, Département des Biotechnologies, Institut Pasteur, 28 rue du Dr Roux, 75724 Paris Cedex 15, France.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Miras
authors.affiliation: Station de Microscopie Electronique, Institut Pasteur, 28 rue du Dr Roux, 75724 Paris Cedex 15, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Gounon
authors.affiliation: Unité de Physiologie Cellulaire and URA 1300 CNRS, Département des Biotechnologies, Institut Pasteur, 28 rue du Dr Roux, 75724 Paris Cedex 15, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Béguin
mesh_terms: D000595:Amino Acid Sequence; D001407:Bacillus / Q000235:genetics; D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins; D001665:Binding Sites; D002473:Cell Wall / Q000378:metabolism; D003013:Clostridium / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D008969:Molecular Sequence Data; D008970:Molecular Weight; D016366:Open Reading Frames; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
chemical_list: D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; C070683:surface layer protein A, Bacteria